diff --git a/Doc/library/subprocess.rst b/Doc/library/subprocess.rst
index 2b5a82e0107fb6..53dfbf827260c9 100644
--- a/Doc/library/subprocess.rst
+++ b/Doc/library/subprocess.rst
@@ -919,9 +919,12 @@ Reassigning them to new values is unsupported:
 
 .. attribute:: Popen.returncode
 
-   The child return code, set by :meth:`poll` and :meth:`wait` (and indirectly
-   by :meth:`communicate`).  A ``None`` value indicates that the process
-   hasn't terminated yet.
+   The child return code. Initially ``None``, :attr:`returncode` is set by
+   a call to the :meth:`poll`, :meth:`wait`, or :meth:`communicate` methods
+   if they detect that the process has terminated.
+
+   A ``None`` value indicates that the process hadn't yet terminated at the
+   time of the last method call.
 
    A negative value ``-N`` indicates that the child was terminated by signal
    ``N`` (POSIX only).